[Python-Dev] cpython (3.2): Issue #14123: Explicitly mention that old style % string formatting has caveats

[Cameron Simpson]

On 27Feb2012 07:13, Nick Coghlan <ncoghlan at gmail.com> wrote:
| On Mon, Feb 27, 2012 at 5:23 AM, Eli Bendersky <eliben at gmail.com> wrote:
| >> It would be nice to call it something else than "printf-style
| >> formatting". While it is certainly modelled on printf(), knowledge of C
| >> or printf is not required to understand %-style formatting, nor even to
| >> appreciate it.
| >
| >
| > +1. The section is already titled "old string formatting operations" so if
| > this name is acceptable it should be reused. If it's not, it should then be
| > consistently changed everywhere.
| 
| I deliberately chose printf-style as being value neutral (whereas
| old-style vs new-style carries a heavier recommendation that you
| should be using the new one). Sure you don't need to know printf to
| understand it, but it needs *some* kind of name, and "printf-style"
| acknowledges its roots.

+1 here from me too: it _is_ printf in roots and several format
specifiers (%d, %s etc). If you know printf you _immediately_ know a lot
about what you can expect, and if you don't you know know a little about
its roots.

| Another value-neutral term is "mod-style",
| which describes how it is invoked (and I believe we do use that in a
| few places already).

A -1 on "mod-style" from me. While it does use the "%" operator symbol, in no
other way is it like the "mod" arithmetic operation.

I think docs _should_ occasionally hint at preferred approaches. The
new new formatting is a deliberate Python change. Without some
rationale/editorial it flies in the face of the "one obvious way to do
things" notion. It shouldn't be overdone, but neither should it be
absent.

Cheers,
-- 
Cameron Simpson <cs at zip.com.au> DoD#743
http://www.cskk.ezoshosting.com/cs/

Ignorance is preferable to error; and he is less remote from the truth
who believes nothing, than he who believes what is wrong.
        - Thomas Jefferson